Recently I've noticed some very cool public artworks in Orewa, however they are not technically officially sanctioned artworks. They are instead knitted artworks, attached to fences, trees and lamp posts, created by artists unknown who definitely put a smile on my face.
The concept of displaying knitting and crocheting in public spaces is commonly referred to as yarn bombing, but has also been called guerrilla knitting, urban knitting and graffiti knitting.
Auckland Libraries has a copy of this book that introduces some of the overseas projects, as well as ideas for different projects to get you started, and there is also a regularly updated blog about different yarn bombing that has taken place all over the globe. You might also want to check out the book : Knit the City.
There were several guerilla knitting sites around Christchurch after the first quake back in September 2010, and you can view some of the photos here, here and here. I've also heard that there have been other sites in Auckland that have had the pleasure of being yarn bombed, but I haven't yet been able to confirm it with my own eyes!